Spray gun



Sept. 12, 1961 J. WAGNER 2,999,646

SPRAY GUN F iled Aug. 26, 1960 2 Sheets-Sheet 1 4a 5/ 27 2 7'6 l O INVENTOR.

JOSE F WAGNER BY A TTORNEV J. WAGNER SPRAY GUN Sept. 12, 1961 2 Sheets-Sheet 2 Filed Aug. 26, 1960 INVENTOR.

JOSEF WA GNE/P tates United Filed Aug. 26, 1960, Ser. No. 52,147 3 Claims. (Cl. 239-332) This invention relates to compressorless spray guns for the atomization of liquids, and more particularly to a piston which is driven by an alternating current oscillatory magnet, the armature of said magnet being pivotable about one end and adjustable in its range of swing about said end to impinge the other end upon the piston which is constantly urged toward a return suction position by a spring.

An object of this invention is to provide an improved spray gun of the kind described having a simply operated quantity regulating device for the liquid which is to be atomized and which utilizes a device for fixing the travel of the outflow valve according to the viscosity of the liquid which is to be atomized.

In brief, my invention contemplates the use of an adjustable regulating knob to vary the linear travel of an impact receiving member which in turn limits the travel of the above referred to armature. By this arrangement control of the quantity of liquid being atomized is provided.

To arrive at the optimum efficiency for atomizing a liquid it is also required that the spray gun be set accord ing to the viscosity of the liquid being sprayed. This is accomplished by axially displacing of a so called guide tube which contains the liquid pump having a pump piston and a pump cylinder. Through these means the travel of the outflow valve in the head of the gun may be varied. The specific means by which this axial displacement is accomplished is an internally threaded roller projecting from the barrel of the gun and which engages external screw threads on the guide tube. Within the guide tube is a connecting rod which operates the pump piston from the armature.

Both the knob and the roller referred to above are spring loaded to eliminate play and thus give an ac curate setting.

A preferred embodiment of my invention is described more fully in the following specification and will easily be understood when taken with the accompanying drawings in which:

FIGURE 1 is a side elevation sectional view taken along the longitudinal axis.

FIGURE 2 is a front elevation view, and

FIGURE 3 is a top plan view.

Studying the drawings in greater particularity it is seen that 1 is the spray gun housing having a suspension hook 2. Within the barrel portion 1A of this housing is a guide tube 3 which contains the pump made up of pump cylinder 4 and an internally fitted pump piston 5. The right end of the guide tube has external threads 6 which are engaged by the internal threads 7 of roller 8 projecting from the barrel portion 1A of the housing. The outer surface of this roller 3 is roughened by projections to provide an easier gripping surface for turning the roller.

Mounted through an axial hole 10 in the guide tube 3 is a connecting rod 11 having a retaining ring 12 about Patented Sept. 12, 1961 its outer end. This connecting rod 11 transmits any force imposed on it to piston rod 5, and vice verse, by means of a bufier cap 13 fastened to rod 5 and spring loaded by a spring 14 bearing on end wall 15 of-cylinder 4.

Through a radial bore 16 in the pump cylinder 4, the liquid to be atomized is sucked from a liquid container 17 through a suction cup 13 and connecting pipe 19. This suction efiect occurs when the pump piston 5 moves away" from the nozzle head, out of the position illustrated in. the drawing, i.e., towards the right. The liquid container 17 is screwed into a retaining lid 20, a portion of which fits around the guide tube 3. Fastening is effected by means of a screw 21 threaded into a hole 22 in the lidi and through a hole 23 in the guide tube to engage the: head part 24 of the cylinder 4 thus immobilizing the; cylinder within the guide tube.

When the roller 8, which contains a recess 25 to carry a spring 26 to eliminate free play and maintain a given setting, is rotated, the guide tube =3 is axially displaced- Depending on whether this tube is moved to the right or the left the piston 5 and the liquid pressure will movea valve head 27 away from its valve seat 28 more or less. This valve head is opposed in its movement by a spring 2-9. During the suction stroke, the spring 29 bearing on the inside 30 of the atomizing nozzle forces the head 27 against seat 28 thus closing the gun.

The atomizing nozzle is of standard construction and therefore will not be gone into in detail. Provision is made for the dispersion of the liquid with air through a nozzle aperture 31 in a closure cap 32 which is screwed on to the pump cylinder 4.

It has been found desirable to have the valve head 27 open more for liquids of thin consistency than for liquids of thick consistency accordingly the roller 8 is adjusted to move the guide tube in accordance with the viscosity of the liquid to be atomized.

The spray gun is driven in a known manner by an electromagnet 4t? whose vertical oscillating armature .41

is supported at its lower end by a projection 42 on a strap of the housing 43 of the magnet. Further support-- ing the armature is an L-shaped leaf spring 44 fastened. approximately at the midpoint of the magnet, to the;

armature at 45. The spring is fixed at one end to the.- housing at 47 and acts to retain the armature against the: projection 42. At the other end of the spring 44 is a bufier 48, preferably of rubber. During the suction stroke this buffer impinges against an adjustable anvil 49' which limits the movement of the armature, the buffer acting to absorb the shocks of said impingements. The suction stroke is actuated by spring 14 which urges connecting rod ll against a buttress 5t fastened to the armature. It is thus seen that the leaf spring 44 acts in conjunction with the attractive force of magnet 40 to urge the armature 41 against the force of spring 14.

The position of anvil 49 can be varied thus regulating the range of movement of the oscillating armature 41. This is effected by means of a regulating knob 51 which is fixed to the shank 52 of the anvil. This shank is threaded and rotatable within a threaded opening'53 in the housing. Like roller 8, the knob is spring loaded by a spring 54 set in recess 55, to prevent free play and to maintain a given setting.

The driving electric current enters the spray gun through cable 56. For greater elficiency the current is first passed through a condenser 57 in the lower part of the handle before entering the magnet. Control over the current is obtained by a normally open push button switch 58.

It will be found that the liquid discharge is greatest when the amplitude of the armature movement is at its greatest. If this amplitude is decreased, the quantity of the pumped liquid will be decreased and the angle of the jet cone issuing from the atomizing head will be greater.

Having shown and described a preferred embodiment of the present invention, by way of example, it should be realized that structural changes could be made and other examples given without departing from either the spirit or scope of this invention.

What I claim is:

l. A spray gun comprising a housing consisting of a hollow body, an electromagnet secured therein, an armature pivotally mounted adjacent the rear of said magnet and extending upwardly, spring means yieldingly urging said armature toward said electromagnet, a handle extending from the lower portion of said body, a push button switch, manually operated, secured in said handle, electrical connections between said switch, magnet and a source of electricity, a barrel extending horizontally from the top of said body above the top of said magnet, a pump therein, that improvement in said pump which comprises a longitudinal guide tube slidably mounted within said barrel, said pump consisting of a pump cylinder having a stepped axial bore, provided with a valve seat and a radial bore, said pump cylinder secured to said longitudinal guide tube, a pump piston slidably mounted for reciprocating movement Within said axial bore, a buffer cap secured to one end of said pump piston, a spring interposed between said butler cap and said pump cylinder yieldingly urging said pump piston to a suction position, suction action being effected by the reciprocating motion of said piston across said radial bore, a connecting rod slidably mounted in said guide tube and abutting said buffer cap on one end, and said armature on the other end, means secured to the lower side of the front portion of said. barrel for holding a depending container, a tube attached to said barrel in communication with said radial bore, the free end of said tube adapted to be immersed in fluid to be sprayed located in said depending container, a closure cap having a nozzle aperature removably secured to said pump cylinder, an atomizing nozzle held against the end of said pump cylinder by said closure cap and positioned to project into said stepped axial bore, a valve head abutting said valve seat, a spring interposed between said valve head and said atomizing nozzle, one end of said pump piston engaging said valve head in opposition to said last mentioned spring, said barrel having a recess, means located in said recess and rotatively engaging said guide tube whereby said guide tube moves horizontally in said barrel and said pump piston moves said valve head away from said valve seat in accordance with the viscosity of the liquid to be atomized.

2. A spray gun comprising a housing consisting of a hollow body, an electromagnet secured therein, an oscillating armature piwtally mounted adjacent the rear and to said magnet and extending upwardly, that improvement in said electromagnet which comprises providing said electromagnet with a projection, said oscillating armature abutting said projection, an L-shaped leaf spring secured on one end to said electromagnet and secured on the ther end midway of the length and to sm'd oscillating armature, a handle extending from the lower portion of said body, a push button switch, manually operated, secured in said handle, electrical connections between said switch, magnet and a source of electricity, a barrel extending horizontally from the top of said body above the top of said magnet, a pump therein, that improvement in said pump which comprises a longitudinal guide tube slidably mounted within said barrel, said pump consisting of a pump cylinder having a stepped axial bore, provided with a valve seat and a radial bore, said pump cylinder secured to said longitudinal guide tube, a pump piston slidably mounted for reciprocating movement Within said axial bore, a buffer cap secured to one end of said pump piston, a spring interposed between said buffer cap and said pump cylinder yieldingly urging said pump piston to a suction position, suction action being effected by the reciprocating motion of said piston across said radial bore, a connecting rod slidably mounted in said guide tube and abutting said bufier cap on one end, and said armature on the other end, means secured to the lower side of the front portion of said barrel for holding a depending container, a tube attached to said barrel in communication with said radial bore, the free end of said tube adapted to be immersed in fluid to be sprayed located in said depending container, a closure cap having a nozzle aperture removably secured to said pump cylinder, an atomizing nozzle held against the end of said pump cylinder by said closure cap and positioned to project into said stepped axial bore, a valve head abutting said valve seat, a spring interposed between said valve head and said atomizing nozzle, one end of said pump piston engaging said valve head in opposition to said last mentioned spring, said barrel having a recess, means located in said recess and rotatively engaging said guide tube whereby said guide tube moves horizontally in said barrel and said pump piston moves said valve head away from said valve seat in accordance with the viscosity of the liquid to be atomized.

3. A spray gun comprising a housing consisting of a hollow body, an electromagnet secured therein, an oscillating armature pivotally mounted adjacent the rear and to said magnet and extending upwardly, that improvement in said electromagnet which comprises providing said electromagnet with a projection, said oscillating armature abutting said projection, an L-shaped leaf spring secured on one end to said electromagnet and secured on the other end midway of the length and to said oscillating armature, a handle extending from the lower portion of said body, a push button switch, manually operated, secured in said handle, electrical connections between said switch, magnet and a source of electricity, a barrel extending horizontally from the top of said body above the top of said magnet, a pump therein, that improvement in said pump which comprises a longitudinal guide tube slidably mounted within said barrel, said pump consisting of a pump cylinder having a stepped axial bore, provided with a valve seat and a radial bore, said pump cylinder secured to said longitudinal guide tube, a pump piston slidably mounted for reciprocating movement Within said axial bore, a buffer cap secured to one end of said pump piston, a spring interposed be.- tween said buffer cap and said pump cylinder yieldingly urging said pump piston to a suction position, suction action being effected by the reciprocating motion of said piston across said radial bore, a connecting rod slidably mounted in said guide tube and abutting said buffer cap on one end, and said armature on the other end, means secured to the lower side of the front portion of said barrel for holding a depending container, a tube attached to said barrel in communication with said radial bore, the free end of said tube adapted to be immersed in fluid to be sprayed located in said depending container, a closure cap having a nozzle aperture removably secured to said pump cylinder, an atomizing nozzle held against the end of said pump cylinder by said closure cap and positioned to project into said stepped axial bore, a valve head abutting said valve seat, a spring interposed between said-valve head and said atomizing nozzle, one end of said pump piston engaging said valve head in opposition guide tube whereby said guide tube moves horizontally ment which in turn limits the movement of said pump in said barrel and said pump piston moves said valve piston to its suction position.

head away from said valve seat in accordance with the viscosity of the liquid to be atomized, a resilient bufier References Cted the file Of thls Patent fastened to said armature adjacent said other end, adjust- 5 UNITED STATES PATENTS able impact receiving means for controlling the move- 2 654 636 Duncan Oct. 6 1953 ment of said armature, said means comprising a shaft 2:811:391 Krebs 1957 threaded through said gun housing and a knob fastened thereto whereby the quantity of liquid being sprayed is FOREIGN PATENTS controlled due to the limitation of the armature move- 10 1,119,645 France Apr. 3, 1956 

